RESUMEN
Some synthetic dyes are fraudulently added into spices to appeal visually to consumers. Food regulations in several countries, including the United States, Australia, Japan and the European Union, strictly prohibit the use of unauthorised synthetic dyes in food. Nevertheless, illegal practices persist, where spices contaminated with potentially carcinogenic dyes have been documented, posing potential health risks to consumers. In the present study, 14 synthetic dyes were investigated through liquid chromatography/tandem mass spectrometry in 252 commercially available spices in the Singapore market. In 18 out of these (7.1%) at least 1 illegal dye was detected at concentrations ranging from 0.010 to 114 mg/kg. Besides potential health risks, presence of these adulterants also reflects the economic motivations behind their fraudulent use. Findings in the present study further emphasise the need for increased public awareness, stricter enforcement, and continuous monitoring of illegal synthetic dyes in spices to ensure Singapore's food safety.
Asunto(s)
Contaminación de Alimentos , Especias , Espectrometría de Masas en Tándem , Especias/análisis , Singapur , Contaminación de Alimentos/análisis , Humanos , Colorantes/análisis , Colorantes/química , Colorantes de Alimentos/análisisRESUMEN
The hollow fiber filter is the primary cell-retention device used in high-density perfusion cell culture and often used in an alternating tangential flow (ATF) configuration. The limited commercially available diaphragm pumps for ATF prevent utilization of vertical space when scaling beyond 500 L. Stacking hollow fiber filters coupled with viscous cell culture imposes vacuum pressure exceeding facility capabilities. Additionally, the longer filter assembly increases the hold-up volume and exceeds the diaphragm pump's fluid exchange capacity. The conventional tangential flow filtration (TFF) configuration circumvents this issue by exchanging culture from the bioreactor and cell-retention device in a unidirectional recirculation loop; however, the increased filter length when scaled up exacerbates the TFF's inherent issue with product retention from Starling flow. Stacking commercially available 20 cm TFF filters to make up the similar single-module length TFF used for the platform 3 and 50 L perfusion process at 41.5 and 65 cm, respectively, attempts to reduce fouling caused by Starling flow. The permeate of a single-module filter is partitioned into short independent segments through serially stacked filters, each harvested separately. By partitioning the permeate, the sieving coefficient increased for both 3 and 50 L scales. Reduction of Starling flow was confirmed with lower total hydraulic membrane resistance throughout the culture. This work demonstrates a method for increasing sieving coefficient and filter capacity by stacking TFF filters with independent permeate streams.
RESUMEN
Dorsal root ganglion stimulation (DRG-S) is a relatively new neuromodulation technique that has shown promising results in the treatment of chronic pain conditions. We present a case of a difficult lead extraction during the explantation of a DRG-S device. The lead was unable to be removed despite multiple attempts until a sheath and stylet were used to facilitate extraction. As DRG-S utilization becomes more widespread, DRG-S device explantation will inevitably become more common. The technique described in this report may be beneficial in certain cases of difficult DRG-S lead extraction.
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Dolor Crónico , Neuralgia , Estimulación de la Médula Espinal , Humanos , Ganglios Espinales/fisiología , Estimulación de la Médula Espinal/métodos , Dolor Crónico/terapia , Neuralgia/terapia , Manejo del Dolor/métodosRESUMEN
Over the past two decades, the introduction of bioorthogonal reactions has transformed the ways in which chemoselective labeling, isolation, imaging, and drug delivery are carried out in a complex biological milieu. A key feature of a good bioorthogonal probe is the ease with which it can be attached to a target compound through bioconjugation. This paper describes the expansion of the utility of a class of unique S-, N-, and O-containing heterocyclooctynes (SNO-OCTs), which show chemoselective reactivity with type I and type II dipoles and divergent reactivities in response to electronic tuning of the alkyne. Currently, bioconjugation of SNO-OCTs to a desired target is achieved through an inconvenient aryl or amide linker at the sulfamate nitrogen. Herein, a new synthetic approach toward general SNO-OCT scaffolds is demonstrated that enables the installation of functional handles at both propargylic carbons of the heterocycloalkyne. This capability increases the utility of SNO-OCTs as labeling reagents through the design of bifunctional bioorthogonal probes with expanded capabilities. NMR kinetics also revealed up to sixfold improvement in cycloaddition rates of new analogues compared to first-generation SNO-OCTs.
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Alquinos , Nitrógeno , Reacción de Cicloadición , Alquinos/química , Nitrógeno/química , Indicadores y Reactivos , AmidasRESUMEN
The biopharmaceutical industry is replacing fed-batch with perfusion processes to take advantage of reduced capital and operational costs due to the operation at high cell densities (HCD) and improved productivities. HCDs are achieved by cell retention and continuous medium exchange, which is often based on the cell-specific perfusion rate (CSPR). To obtain a cost-productive process the perfusion rate must be determined for each process individually. However, determining optimal operating conditions remain labor-intensive and time-consuming experiments, as investigations are performed in lab-scale perfusion bioreactors. Small-scale models such as microwell plates (MWPs) provide an option for screening multiple perfusion rates in parallel in a semi-perfusion mimic. This study investigated two perfusion rate strategies applied to the MWP platform operated in semi-perfusion. The CSPR-based perfusion rate strategy aimed to maintain multiple CSPR values throughout the cultivation and was compared to a cultivation with a perfusion rate of 1 RV d-1. The cellular performance was investigated with the dual aim (i) to achieve HCD, when inoculating at conventional and HCDs, and (ii) to maintain HCDs, when applying an additional manual cell bleed. With both perfusion rate strategies viable cell concentrations up to 50 × 106 cells mL-1 were achieved and comparable results for key metabolites and antibody product titers were obtained. Furthermore, the combined application of cell bleed and CSPR-based medium exchange was successfully shown with similar results for growth, metabolites, and productivities, respectively, while reducing the medium consumption by up to 50% for HCD cultivations.
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Reactores Biológicos , Cricetulus , Células CHO , Animales , Perfusión/métodos , Perfusión/instrumentación , Técnicas de Cultivo de Célula/métodos , Técnicas de Cultivo de Célula/instrumentación , Ensayos Analíticos de Alto Rendimiento/métodos , Recuento de Células , Técnicas de Cultivo Celular por Lotes/métodos , Técnicas de Cultivo Celular por Lotes/instrumentaciónRESUMEN
As the need for higher volumetric productivity in biomanufacturing grows, biopharmaceutical companies are increasingly investing in a perfusion cell culture process, most commonly one that uses a hollow fiber filter as the cell retention device. A current challenge with using hollow fiber filters is fouling of the membrane, which reduces product sieving and can increase transmembrane pressure (TMP) past process limitations. In this work, the impact of hollow fiber filter geometries on product sieving and hydraulic membrane resistance profiles is evaluated in a tangential flow filtration (TFF) perfusion system. The hollow fibers tested had lengths ranging from 19.8 to 41.5 cm, inner diameters (IDs) ranging from 1.0 to 2.6 mm, and pore sizes of 0.2 or 0.65 µm. The results showed that the shortest hollow fibers experienced higher product sieving while larger IDs contributed to both higher product sieving and lower hydraulic membrane resistances, illustrating the impact of filter geometry on process performance. The results also showed 0.2 µm pore size filters maintain higher product sieving, but also higher membrane resistances compared to 0.65 µm pore size filters. This study highlights the need for optimized hollow fiber filter geometries to maximize use of the membrane area, which in turn can reduce production costs and increase scalability of the perfusion process.
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Técnicas de Cultivo de Célula , Filtración , Filtración/métodos , Filtración/instrumentación , Técnicas de Cultivo de Célula/métodos , Técnicas de Cultivo de Célula/instrumentación , Membranas Artificiales , Perfusión , Porosidad , Animales , Cricetulus , Células CHO , Reactores Biológicos , Diseño de EquipoRESUMEN
The promise of continuous processing to increase yields and improve product quality of biopharmaceuticals while decreasing the manufacturing footprint is transformative. Developing and optimizing perfusion operations requires screening various parameters, which is expensive and time-consuming when using benchtop bioreactors. Scale-down models (SDMs) are the most feasible option for high-throughput data generation and condition screening. However, new SDMs mimicking perfusion are required, enabling experiments to be run in parallel. In this study, a method using microwell plates (MWP) operating in semi-perfusion mode with an implemented cell bleed step is presented. A CHO cell line was cultivated in a 24-well MWP (Vw = 1.2 mL) and grown at four high cell density (HCD) setpoints. Quasi steady-state condition was obtained by manually performing cell bleeds followed by a total medium exchange after centrifugation. Further, two HCD setpoints were scaled up (VW = 30 mL), comparing a squared six-well deepwell plate (DWP) to shake flasks (SF). This evaluation showed comparable results between systems (DWP vs. SF) and scales (MWP vs. DWP + SF). The results show that the well-plate-based methods are suitable to perform HCD and quasi steady-state cultivations providing a robust solution to industrially relevant challenges such as cell clone and media selection.
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Cricetulus , Ensayos Analíticos de Alto Rendimiento , Células CHO , Animales , Ensayos Analíticos de Alto Rendimiento/métodos , Reactores Biológicos , Técnicas de Cultivo de Célula/métodos , Técnicas de Cultivo de Célula/instrumentación , Recuento de CélulasRESUMEN
In this study, an advanced ultra-high performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was developed for quantifying ethoxyquin (EQ). The approach employed a distinctive antioxidant added extraction step designed to prevent ethoxyquin decomposition and maintain analytical precision. This method effectively determines residue levels of EQ in eggs, processed egg products, poultry muscle, salmon, and liquid milk. The method was shown to have a limit of quantitation (LOQ) for eggs, milk, salmon, and chicken muscle of 1.5 µg/kg, 1.9 µg/kg, 2.1 µg/kg, and 1.2 µg/kg, respectively. The recoveries of EQ ranged from 79.2% to 107.6%, with a relative standard deviation (RSD) below 8.4%. A surveillance study for the presence of EQ in different types of eggs and poultry muscle available in Singapore was conducted and a total of 140 samples were tested. EQ residues in all samples were found to be below the U.S. Food and Drug Administration (FDA) MRLs of 500 µg/kg. Some samples of salted and preserved eggs from China were detected with higher concentration of EQ.
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Etoxiquina , Espectrometría de Masas en Tándem , Animales , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Etoxiquina/análisis , Cromatografía Liquida/métodos , Aves de Corral , Singapur , SalmónRESUMEN
Rationale: Chronic infection and inflammation shapes the airway microbiome in bronchiectasis. Utilizing whole-genome shotgun metagenomics to analyze the airway resistome provides insight into interplay between microbes, resistance genes, and clinical outcomes. Objectives: To apply whole-genome shotgun metagenomics to the airway microbiome in bronchiectasis to highlight a diverse pool of antimicrobial resistance genes: the "resistome," the clinical significance of which remains unclear. Methods: Individuals with bronchiectasis were prospectively recruited into cross-sectional and longitudinal cohorts (n = 280), including the international multicenter cross-sectional Cohort of Asian and Matched European Bronchiectasis 2 (CAMEB 2) study (n = 251) and two independent cohorts, one describing patients experiencing acute exacerbation and a further cohort of patients undergoing Pseudomonas aeruginosa eradication treatment. Sputum was subjected to metagenomic sequencing, and the bronchiectasis resistome was evaluated in association with clinical outcomes and underlying host microbiomes. Measurements and Main Results: The bronchiectasis resistome features a unique resistance gene profile and increased counts of aminoglycoside, bicyclomycin, phenicol, triclosan, and multidrug resistance genes. Longitudinally, it exhibits within-patient stability over time and during exacerbations despite between-patient heterogeneity. Proportional differences in baseline resistome profiles, including increased macrolide and multidrug resistance genes, associate with shorter intervals to the next exacerbation, whereas distinct resistome archetypes associate with frequent exacerbations, poorer lung function, geographic origin, and the host microbiome. Unsupervised analysis of resistome profiles identified two clinically relevant "resistotypes," RT1 and RT2, the latter characterized by poor clinical outcomes, increased multidrug resistance, and P. aeruginosa. Successful targeted eradication in P. aeruginosa-colonized individuals mediated reversion from RT2 to RT1, a more clinically favorable resistome profile demonstrating reduced resistance gene diversity. Conclusions: The bronchiectasis resistome associates with clinical outcomes, geographic origin, and the underlying host microbiome. Bronchiectasis resistotypes link to clinical disease and are modifiable through targeted antimicrobial therapy.
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Bronquiectasia , Bronquiectasia/fisiopatología , Bronquiectasia/microbiología , Bronquiectasia/tratamiento farmacológico , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Transversales , Estudios Longitudinales , Antibacterianos/uso terapéutico , Estudios Prospectivos , Microbiota/genética , Pseudomonas aeruginosa/genética , Esputo/microbiología , Metagenómica/métodos , Adulto , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/complicacionesRESUMEN
Resumo Objetivos Descrever a experiência da implementação de um programa de treinamento de assistente de pesquisa voluntário para graduandos canadenses de Enfermagem, objetivando o desenvolvimento de habilidades de comunicação verbal e escrita, métodos de pesquisa e análise de dados, pensamento crítico e resolução de problemas, assim como o planejamento de suas carreiras e o avanço de seus papéis relacionados à pesquisa e às oportunidades administrativas e de liderança. Método Estudo descritivo com relato de experiência sobre o processo de treinamento para um novo papel profissional relativo ao engajamento dos graduandos em 11 oficinas, cada uma com duração de uma hora e o processo de apoiá-los para assumir papéis profissionais e de liderança. Resultados Os graduandos demonstraram comprometimento em todas as fases do treinamento. Destaca-se, ainda, o interesse por assumirem a liderança em atividades práticas que redefinem seu perfil profissional. Essa experiência contribuiu para construir e nutrir relações intelectuais docentes-graduandos. Os graduandos expandiram suas redes profissionais e a relação com o mentor de carreira, estão desenvolvendo suas habilidades práticas e relataram confiança em se candidatar para cargos de assistentes de pesquisa. Conclusão e implicações para a prática O treinamento pode instrumentalizá-los para escolhas de planos de carreira, ingresso no mercado de trabalho e a construção de plano para desenvolvimento profissional. O desejo genuíno dos docentes de Enfermagem, apoiando uma nova geração de enfermeiros, culminou nessa experiência de empoderamento mútuo.
Resumen Objetivos Informar sobre la experiencia de un equipo de profesionales de enfermería y desarrollo profesional en la implementación de un programa de asistente voluntario de investigación para estudiantes universitarios canadienses de pregrado en enfermería con el objetivo de desarrollar la comunicación escrita y verbal, métodos de investigación, análisis de datos, pensamiento crítico y habilidades de resolución de problemas, así como en su planificación y avance profesional para funciones relacionadas con la investigación y oportunidades de empleo administrativo y de liderazgo. Método Un diseño descriptivo con el informe de la experiencia de los investigadores de enfermería y desarrollo profesional sobre el proceso de apoyo para la formación de los estudiantes para un nuevo rol profesional. La experiencia se refiere a 11 talleres que durarán una hora sobre los temas relacionados con la investigación. Resultados Los estudiantes demostraron compromiso con la capacitación. Relevante es su interés en liderar actividades prácticas para redefinir su perfil profesional. Esta experiencia contribuyó a construir y fomentar relaciones significativas e intelectuales entre los profesores y los estudiantes. Los estudiantes amplían sus redes profesionales y obtienen una relación con un mentor de carrera. Conclusión e implicaciones para la práctica La capacitación puede equipar mejor a los estudiantes para elegir trayectorias profesionales, entrar en el mercado laboral y elaborar un plan para el avance profesional. Fue el deseo genuino de los profesores de enfermería de apoyar a una nueva generación de enfermeras que culminó en esta experiencia de empoderamiento mutuo.
Abstract Objective To describe the experience of implementing a research assistant program for Canadian undergraduate nursing students, which aimed to develop written and verbal communication, critical thinking and problem-solving skills, as well as knowledge of various research methods. Engagement in this program was intended to support students' career planning and advancement in research related roles, including administrative and leadership employment opportunities. Method A descriptive design with the report of experience of nursing researchers and career advisers pertaining to: engagement in an 11 one-hour research focused workshop; and the process of supporting students to assume professional and leadership roles. Results Students demonstrated commitment to the training program throughout its phases. They expressed interest in leading practical activities to redefine their professional profile. This experience contributed to building and nurturing intellectual teacher-student relationships. Students are expanding their professional networks and a relationship with a career mentor, while demystifying the research assistant role. Students are developing practical skills and reporting confidence in applying for research assistant positions. Conclusion and Implications for practice Participating in the training program better equips students for choosing their career path, entering the job market, and building a plan for further career advancement. Nursing faculty's genuine desire for and purposeful actions to support a new generation of nurses informed this mutually empowering experience.